Well, CE3 wasn't going to be ground-breaking like CE1 to CE2 if that's what you're after.
CE3 is simply an optimized engine, from what I gathered, with some improved/new features. So really, no differences except it will run better for everyone, without the need of a super computer.
But I like what these guys do. Serious simulations, which although may never come to us, look really well done.